Devices and Formulations for Detecting, Screening and Monitoring Levels of Certain Constituents in Bodily Fluids and Method

ABSTRACT

A device is disclosed for conducting a non-invasive analysis of a bodily fluid to determine the presence and level of a certain constituent carried by the bodily fluid. An indicator formulation of the device changes color in response to exposure to the constituent to provide a visible indication of the presence and level of the constituent carried by the bodily fluid. A carrier substrate of the device is constructed of a material having voids providing a high void volume within the substrate. The device is made by applying a chromagen to the carrier substrate to create a chromagen-laden carrier member. Then, a selected reagent having a particular constituent-specific formulation is applied to the chromagen-laden member. The selected reagent then combines with the chromagen, thereby establishing the indicator formulation within the carrier substrate in place for reception of a sample of the bodily fluid.

This application is a divisional application of U.S. Ser. No.13/278,306, filed Oct. 21, 2011, and further claims the benefit of U.S.Provisional Patent Application Ser. No. 61/455,528, filed Oct. 23, 2010,U.S. Provisional Patent Application Ser. No. 61/455,531, filed Oct. 23,2010, U.S. Provisional Patent Application Ser. No. 61/455,532, filedOct. 23, 2010, and U.S. Provisional Patent Application Ser. No.61/462,890, filed Feb. 9, 2011, the entire disclosures of which areincorporated herein by reference thereto.

The present invention relates generally to devices and formulations forreagents employed in such devices that enable detecting, screening andmonitoring levels of certain constituents in bodily fluids sampled fromhumans and animals, and pertains, more specifically, to the constructionand manufacture of such devices.

In two earlier U.S. Pat. Nos. 7,824,344 and 7,993,283, the substance ofwhich patents is incorporated herein by reference thereto, there isdisclosed methods and apparatus for conducting a non-invasive analysisof saliva. The present invention provides formulations and devices thatenable a user to employ a bodily fluid, such as saliva or another oralfluid, serum or plasma, utilizing devices that provide color changes toindicate the presence and level of a certain constituent in the bodilyfluid. Further, the present invention provides methods of constructionand manufacture that enable such devices to be made available forwidespread use for detecting, screening or monitoring the presence andlevel of any one of a plurality of certain constituents with increasedease and economy. As such, the present invention attains several objectsand advantages, some of which are summarized as follows: Providesdevices of simplified construction for widespread use in detecting,screening and monitoring the presence and level of any selected one of aplurality of certain constituents in bodily fluids; enables anexceptionally rapid response in a quick and easy non-invasive procedurefor determining the presence and level of a particular constituent in abodily fluid; provides for the economical manufacture and distributionof devices capable of detecting, screening and monitoring the presenceof certain constituents in bodily fluids; makes available a simplifiedvisual reading of a color change to determine the presence and level ofa certain constituent in a bodily fluid; provides an economical andreliable device for simplified use in detecting, screening or monitoringthe presence of a selected certain constituent in a bodily fluid;encourages widespread use to the benefit of a larger number of users whocan enjoy greater economy and convenience in reaching and maintaininghigher goals in healthcare.

The above objects and advantages are attained by the present invention,which may be described briefly as a method of making a device forconducting a non-invasive analysis of a bodily fluid to determine thepresence and the level of a certain constituent carried by the bodilyfluid, the device including an indicator formulation capable of changingcolor in response to exposure to the certain constituent to provide avisible indication of the presence and the level of the certainconstituent carried by the bodily fluid, the method comprising:providing a carrier substrate of a material having voids establishing ahigh void volume within the carrier substrate; applying a chromagenformulation to the carrier substrate to create a chromagen-laden carriermember; and subsequently applying to the chromagen-laden carrier membera selected reagent having a particular constituent-specific formulationto combine the selected reagent with the chromagen formulation appliedto the carrier substrate, thereby establishing the indicator formulationwithin the carrier substrate in place for reception of a sample of thebodily fluid later placed upon the carrier substrate.

In addition, the invention provides a device for conducting anon-invasive analysis of a bodily fluid to determine the presence andthe level of a certain constituent carried by the bodily fluid, thedevice including an indicator formulation capable of changing color inresponse to exposure to the certain constituent to provide a visibleindication of the presence and the level of the certain constituentcarried by the bodily fluid, the device comprising: a carrier substrateof a material having voids establishing a high void volume within thecarrier substrate; and an indicator formulation carried by the carriersubstrate, the indicator formulation consisting essentially of achromagen formulation and a constituent-specific formulation selectedfrom formulations responsive to levels of any one of a plurality ofdifferent certain constituents.

The invention will be understood more fully, while still further objectsand advantages will become apparent, in the following detaileddescription of preferred embodiments of the invention illustrated in theaccompanying drawing, in which:

FIG. 1 is a pictorial view of a device constructed in accordance withthe present invention;

FIG. 2 is an enlarged, somewhat diagrammatic, cross-sectional view takenalong line 2-2 of FIG. 1;

FIG. 3 is a flow diagram illustrating a method of the present invention;

FIG. 4 is a plan view of another device constructed in accordance withthe present invention;

FIG. 5 is a pictorial view showing use of the device of FIG. 4;

FIG. 6 is a pictorial view showing the use of still another deviceconstructed in accordance with the present invention; and

FIG. 7 is a pictorial view showing the use of yet another deviceconstructed in accordance with the present invention.

Referring now to the drawing, and especially to FIGS. 1 and 2 thereof, adevice constructed in accordance with the present invention is shown at20 and is seen to include a carrier substrate in the form of a pad 22 ofa material having voids 24 establishing a high void volume within thepad 22. An indicator formulation is carried by the pad 22 and isillustrated at 30 in the form of a layer 32 carried by fibers 34 of thematerial, in juxtaposition with voids 24 within the pad 22. Indicatorformulation 30 consists essentially of a chromagen formulation and areagent having a constituent-specific formulation selected fromformulations responsive to one of a plurality of constituents, as willbe set forth in greater detail below. Suffice it to say at this juncturethat the reagent having a constituent-specific formulation and thechromagen formulation are combined within the pad 22 such that theindicator formulation 30 is capable of changing color in response toexposure to the certain constituent to provide a visible indication onthe pad 22 of the presence and the level of the certain constituentcarried by a sample of a bodily fluid applied to the pad 22.

Thus, upon applying a sample of a bodily fluid, such as a saliva sample,to the pad 22, placed at a target area 36 of the device 20, theoccurrence of a visible color change will provide at least a qualitativeindication of the presence of the particular specific constituent towhich the constituent-specific formulation will react. An absence of anyvisible color change will indicate that the specific constituent is notpresent in any significant amount in the saliva sample.

The preferred material for pad 22 is a non-woven fibrous material whichprovides the requisite high void volume. The high void volume providespad 22 with the ability to absorb rapidly the sample of bodily fluidapplied to the target area 36, to enable rapid interaction of the samplewith the indicator formulation 30, and to maximize exposure of theinteracting sample and indicator formulation to ambient air forpromoting a quick response through accelerating a reaction between thecertain constituent carried by the sample and the indicator formulation.Non-woven synthetic polymeric materials are available commercially, onesuch material being a non-woven polyester fibrous material. Suitableglass-fiber non-woven fibrous materials and cellulose non-woven fibrousmaterials also are available commercially in forms suitable for use inthe construction of pad 22. The preferred materials are chosen toprovide pad 22 with a void volume within a range of about eight totwelve percent of the total volume of the material.

Device 20 is constructed in several different variations such that onevariation is available to provide a visible color change as anindication of at least the presence of a corresponding one of severalcertain constituents, namely, glucose, cholesterol, ethanol, uric acidand galactose, and, preferably, the level of the certain constituent, inthe sample of bodily fluid applied to the target area 36 of the pad 22.Each variation requires that the pad 22 carry a formulation specific tothe constituent to be detected, as a component of the indicatorformulation 30; however, the chromagen formulation remains unchangedamong the different variations of the pad 22 so that the same chromagenformulation can serve in every variation of the pad 22. Accordingly, themanufacture and distribution of the devices 20 is simplified andrendered more economical, as will be described below.

Turning now to FIG. 3, as well as to FIGS. 1 and 2, pad 22 of device 20is manufactured by first applying to the material of pad 22 thechromagen formulation, as seen in step 40, to create a chromagen-ladencarrier member in the form of pad 22 with the chromagen formulationplaced in juxtaposition with voids 24 of the pad 22. Subsequently, aselected reagent having a particular constituent-specific formulation isapplied to the chromagen-laden carrier member, as indicated at step 42,to combine the selected reagent with the chromagen formulation appliedearlier to the material of pad 22, thereby establishing the indicatorformulation 30 within the completed pad 22. Pad 22 is placed at targetarea 36 of device 20 for reception of the sample of bodily fluid uponthe pad 22. Since the chromagen formulation remains the same for allvariations of the device 20, economies are realized in the manufacturingprocess which requires only one component common to all variations andonly one station for the application of that common component; however,further economy and convenience are accomplished by the ability to storethe intermediate product, that is, the material of pad 22 with theapplied chromagen formulation, is stored, as seen in step 44.Subsequently applying any selected one of the constituent-specificformulations is applied, at a later time, in accordance with therequirement for any number of a particular device or particular devices,the completed carrier member with the indicator formulation beingavailable at step 46. The ability to have on hand a supply of the basicchromagen-laden carrier member for subsequent combination with aselected constituent-specific formulation, as opposed to immediatelycreating an inventory of completed carrier members, as indicated byprocedure 48, reduces the necessity for maintaining on-hand a largeinventory of every variety of completed device 20 while increasing theflexibility and turn-around time of filling the demand for any number ofdevices 20 in any one of the different varieties.

With respect to the varieties identified above, the common chromagenformulation consists essentially of the following components, in anexample prepared as follows: Approximately equal volumes of about 0.05to 0.5 M MBTH in distilled water is mixed with about 0.05 to 0.5 M DMABin ethanol. The mixture is impregnated into the material of the carriermember and the impregnated material subsequently is dried, leaving thematerial with the chromagen formulation coated upon the fibers of thematerial.

With respect to each of the varieties identified above, the followingconstituent-specific formulations are effective, and an example of thepreparation of each is set forth below:

For the determination of the presence and level of glucose as thecertain constituent in a bodily fluid, a constituent-specificformulation consists essentially of the following components, in anexample prepared as follows: Dissolve approximately equal amounts of theenzymes glucose oxidase with an activity of approximately 200 U/mg andperoxidase with an activity of approximately 200 U/mg in distilled waterin the presence of approximately equal amounts of 0.05 to 0.5 M HEPES, ablend of surface active agents within the range of about 0.1% to 10%each, and a stabilizer, the preferred stabilizer being a PVP/copolymercomplex in which the copolymer is methylvinylether/maleic anhydride,available commercially under the trademark GANTREZ®, the complex beingprepared from 5% PVP K30 in distilled water and 5% GANTREZ® AN 139 at apH of about 7.5. The prepared constituent-specific formulation then isimpregnated into the material previously impregnated with the chromagenformulation to complete a pad 22 having an indicator formulation 30responsive to the presence and level of glucose in an applied sample ofa bodily fluid.

For the determination of the presence and level of cholesterol as thecertain constituent in a bodily fluid, a constituent-specificformulation consists essentially of the following components, in anexample prepared as follows: Dissolve approximately equal amounts of theenzymes cholesterol esterase with an activity of approximately 180 U/mgand peroxidase with an activity of approximately 200 U/mg and twice asmuch cholesterol oxidase with an activity of approximately 47 U/mg) indistilled water in the presence of approximately equal amounts of 0.05to 0.5 M HEPES, a blend of surface active agents within the range ofabout 0.1% to 10% each and a stabilizer, the preferred stabilizer beinga PVP/copolymer complex in which the copolymer ismethylvinylether/maleic anhydride, available commercially under thetrademark GANTREZ®, the complex being prepared from 5% PVP K30 indistilled water and 5% GANTREZ® AN 139 at a pH of about 7.5. Theprepared constituent-specific formulation then is impregnated into thematerial previously impregnated with the chromagen formulation tocomplete a pad 22 having an indicator formulation 30 responsive to thepresence and level of cholesterol in an applied sample of a bodilyfluid.

For the determination of the presence and level of ethanol as thecertain constituent in a bodily fluid, a constituent-specificformulation consists essentially of the following components, in anexample prepared as follows: Mix together approximately equal amounts ofabout 1% to 20% PVP K30 in distilled water, about 0.5% to 5% ethoxylatedsurfactant in distilled water and about 0.05 to 0.5 M phosphate bufferat pH 8.5 together with one-half the same amount of alcohol oxidase withan activity of approximately 400 U/ml and one-quarter the same amount ofperoxidase with an activity of approximately 200 U/mg. The preparedconstituent-specific formulation then is impregnated into the materialpreviously impregnated with the chromagen formulation to complete a pad22 having an indicator formulation 30 responsive to the presence andlevel of ethanol in an applied sample of a bodily fluid.

For the determination of the presence and level of uric acid as thecertain constituent in a bodily fluid, a constituent-specificformulation consists essentially of the following components, in anexample prepared as follows: In approximately one-hundred ml of 0.05 to0.5 M phosphate buffered saline at pH 6.4, mix together approximatelyten mg of uricase, fifteen mg of ascorbate oxidase and about six mg ofperoxidase with an activity of approximately 200 U/mg. The preparedconstituent-specific formulation then is impregnated into the materialpreviously impregnated with the chromagen formulation to complete a pad22 having an indicator formulation 30 responsive to the presence andlevel of uric acid in an applied sample of a bodily fluid.

For the determination of the presence and level of galactose as thecertain constituent in a bodily fluid, a constituent-specificformulation consists essentially of the following components, in anexample prepared as follows: Mix together approximately five ml each ofabout 0.05 to 0.5 M phosphate buffer at pH 7.0, peroxidase with anactivity of about 200 U/mg, and ethanol (95%) together with abouttwenty-five ml of 10% polyvinyl alcohol in distilled water and 4200units of galactose oxidase. The prepared constituent-specificformulation then is impregnated into the material previously impregnatedwith the chromagen formulation to complete a pad 22 having an indicatorformulation 30 responsive to the presence and level of galactose in anapplied sample of a bodily fluid.

In the embodiment of the invention illustrated in FIG. 4, a disk-shapeddevice 100 includes a pad 110 constructed of the material previouslydescribed in connection with pad 22 of device 20. Pad 110 provides atarget area 112 which, in device 110, is substantially surrounded by anintegrated color gauge 114 having patches 116 of different colors thatcan be matched visually with a color change at the target area 112. Asin the devices disclosed in the aforesaid U.S. Pat. Nos. 7,824,344 and7,993,283, alpha-numeric characters may be displayed in juxtapositionwith the patches 116 for a direct reading of the level detected. In thismanner, device 100 provides a simple semi-qualitative/semi-quantitativemeasure of the presence and level of a particular certain constituentcarried by a sample of bodily fluid applied to the target area 112. Thesemi-qualitative/semi-quantitative indication, while more comprehensivethan the generally qualitative indication provided by device 20described above, is convenient, as shown in FIG. 5 where the device 100is placed readily within the palm 118 of a user's hand, but not ascomprehensive as the indication provided by other embodiments of theinvention, as set forth below.

In the embodiment shown in FIG. 6, a device 120 is constructed asdescribed in detail in the aforesaid U.S. Pat. Nos. 7,824,344 and7,993,283, and is inserted into a reader 122 that employs an algorithmwhich converts a sensed color change into an accurate digital readout ata display 124, for a more accurate quantitative evaluation of thepresence and level of a particular certain constituent carried by abodily fluid sample.

In the embodiment illustrated in FIG. 7, a device 130 carries a strip132 similar in construction to pad 22 described above, and arranged in acoil 134 held within the device 130. A sample of bodily fluid is appliedto the strip 132, at a target area registered with an access door 140through which the sample is passed to the strip 132. A color change issensed and an algorithm converts the sensed color change into anaccurate digital readout at a display 142. The used portion 144 of thestrip 132 is advanced through a slot 146 and is torn off and discarded.

The embodiments illustrated in FIGS. 6 and 7 are conveniently availableto a user wishing to control and maintain weight levels. Thus, forexample, upon use of a device 120 or 130 in connection with monitoringthe level of glucose in a bodily fluid, such as saliva, the algorithmsprovided by these embodiments can convert the detected glucose levelinto glycemic control readily understood and employed by a user inconnection with a weight control regimen. In this manner, the user isprovided with information to refine glycemic control, enabling the userto adjust diet, supplement intake and exercise for the purpose ofglycemic control and weight control.

It will be seen that the present invention attains all of the objectsand advantages summarized above, namely: Provides devices of simplifiedconstruction for widespread use in detecting, screening and monitoringthe presence and level of any selected one of a plurality of certainconstituents in bodily fluids; enables an exceptionally rapid responsein a quick and easy non-invasive procedure for determining the presenceand level of a particular constituent in a bodily fluid; provides forthe economical manufacture and distribution of devices capable ofdetecting, screening and monitoring the presence of certain constituentsin bodily fluids; makes available a simplified visual reading of a colorchange to determine the presence and level of a certain constituent in abodily fluid; provides an economical and reliable device for simplifieduse in detecting, screening or monitoring the presence of a selectedcertain constituent in a bodily fluid; encourages widespread use to thebenefit of a larger number of users who can enjoy greater economy andconvenience in reaching and maintaining higher goals in healthcare.

It is to be understood that the above detailed description of preferredembodiments of the invention is provided by way of example only. Variousdetails of design, construction and procedure may be modified withoutdeparting from the true spirit and scope of the invention, as set forthin the appended claims.

1. A device for conducting a non-invasive analysis of a bodily fluid todetermine the presence and the level of a certain constituent carried bythe bodily fluid, the device including an indicator formulation capableof changing color in response to exposure to the certain constituent toprovide a visible indication of the presence and the level of thecertain constituent carried by the bodily fluid, the device comprising:a carrier substrate of a material having voids establishing a high voidvolume within the carrier substrate; and an indicator formulationcarried by the carrier substrate, the indicator formulation consistingessentially of a chromagen formulation and a constituent-specificformulation selected from formulations responsive to levels of any oneof a plurality of different certain constituents.
 2. The device of claim1 wherein the different certain constituents are glucose, cholesterol,ethanol, uric acid, and galactose.
 3. The device of claim 2 wherein thechromagen formulation consists essentially of approximately equal partsof 0.05 to 0.5 M MBTH and 0.05 to 0.5 M DMAB.
 4. The device of claim 3wherein the certain constituent is glucose and the constituent-specificformulation consists essentially of approximately equal amounts of theenzymes glucose oxidase with an activity of approximately 200 U/mg, andperoxidase with an activity of approximately 200 U/mg in the presence ofapproximately equal amounts of 0.05 to 0.5 M HEPES, a blend of surfaceactive agents within the range of about 0.1% to 10% each, and astabilizer.
 5. The device of claim 3 wherein the certain constituent ischolesterol and the particular constituent-specific formulation consistsessentially of a selected amount of the enzyme cholesterol esterase withan activity of approximately 180 U/mg, the same selected amount ofperoxidase with an activity of approximately 200 U/mg, and twice theselected amount of cholesterol oxidase with an activity of approximately47 U/mg in the presence of approximately equal amounts of 0.05 to 0.5 MHEPES, a blend of surface active agents within the range of about 0.1%to 10% each, and a stabilizer.
 6. The device of claim 3 wherein thecertain constituent is ethanol and the particular constituent-specificformulation consists essentially of approximately equal selected amountsof about 1% to 20% PVP K30, about 0.5% to 5.0% ethoxylated surfactantand about 0.05 to 0.5 M phosphate buffer at pH 8.5, one-half theselected amount of alcohol oxidase with an activity of approximately 400U/ml and one-quarter the selected amount of peroxidase with an activityof approximately 200 U/mg.
 7. The device of claim 3 wherein the certainconstituent is uric acid and the particular constituent-specificformulation consists essentially of approximately ten parts of uricase,about fifteen parts of ascorbate oxidase and about six parts ofperoxidase in 0.05 to 0.5 M phosphate buffered saline at pH 6.4.
 8. Thedevice of claim 3 wherein the certain constituent is galactose and theparticular constituents-specific formulation consists essentially ofapproximately five parts of about 0.05 to 0.5 M phosphate buffer at pH7.0, approximately five parts of peroxidase with an activity ofapproximately 200 U/mg, and approximately five parts of ethanol, inabout twenty-five parts of 10% polyvinyl alcohol, and 4200 units ofgalactose oxidase.
 9. The device of claim 1 wherein the material of thecarrier substrate comprises a non-woven material.
 10. The device ofclaim 9 wherein the carrier substrate has a total volume and the highvoid volume is within a range of about eight to twelve percent of thetotal volume.
 11. The device of claim 1 wherein the material of thecarrier substrate comprises a non-woven synthetic polymeric material.12. The device of claim 11 wherein the synthetic polymeric material is apolyester.
 13. The device of claim 12 wherein the carrier substrate hasa total volume and the high void volume is within a range of about eightto twelve percent of the total volume.
 14. The device of claim 9 whereinthe material of the carrier substrate comprises glass-fiber.
 15. Thedevice of claim 14 wherein the carrier substrate has a total volume andthe high void volume is within a range of about eight to twelve percentof the total volume.